Implementation of the invention is applicable to a very large variety of active medical devices, implantable or not, including in particular, in addition to the cardiac prostheses: neurological apparatuses, pumps for distribution of medical substances, cochlear implants, implanted biological sensors, etc. These devices comprise a case or a “generator” connected electrically and mechanically to one or more probes equipped with electrodes, whose role is to distribute energy to tissue, e.g., the heart.
There are standardized systems of connection, making possible interchangeability of probes and the generators produced by various manufacturers. The “IS-1” standard, for example, defines a certain number of dimensional and electric specifications relating to probes delivering impulses of low stimulation voltage.
For defibrillation probes or cardioversion, where electrical constraints are more severe given the high energy delivered by the generator to the probes, another standard known as “DF-1” defines the dimensional and electric specifications of the connection system.
In the case of “mono-body” probes, equipped at the same time with both stimulation (or sensing) electrodes and shock electrodes, it is foreseen, for example, a terminal with the IS-1 standard connected to a right ventricular distal detection/stimulation electrode, and two terminals with the DF-1 standard connected to two shock electrodes, respectively, a right ventricular electrode, and a “supraventricular” electrode, which is intended to be positioned in the higher vena cava for application of shock to the atrium. The complexity of such probes is expected to become even more complex in the future, in particular with development of multisite type devices and intracardiac sensors, such as peak endocavitary acceleration (PEA) sensors. The realization of mono-body probes integrating all these functions and becoming increasingly complex led to a multiplication of the connection terminals with in addition different standards between the terminals.
Work is currently underway for definition of a new connection standard for such probes, which would allow a single terminal carrying a plurality of contacts to simultaneously ensure establishment of connections at the various output of the generator for all energy levels: sensing of depolarization signals, application of stimulation impulses, or application of cardioversion or defibrillation shocks.
It is in particular considered, within the framework of this work, to define a standard where the single terminal would be of the “isodiameter” type, i.e., a uniform cylindrical form intended to be inserted into a homologous cavity within the generator, with sealing functions performed by elements incorporated in the head of the connector, unlike IS-1 and DF1 standards, which, on the contrary, impose the presence on each relief terminal of a sealing formed on the flexible insulating sleeve.
The realization of such an isodiameter terminal with multiple contacts, however, implies the resolution of many manufacturing problems, in particular because of manufacturing difficulties, taking into account the small dimensions (the considered diameter being only 3.2 mm) and the need for carrying out the electric connections between the contacts of the terminal and the various corresponding conductors in the probe while respecting the constraints of safety and reliability of this type of product, which is intended to be implanted in a patient. Another manufacturing aspect is the complexity related to the need to design and manufacture terminals adapted to various types of probes, for example, probes including or not including PEA sensors with configurations of bipolar or multipolar stimulation electrodes, etc. Each type of probe will correspond to a different terminal, or a different terminal plugging scheme, making more complex, and thus more expensive, manufacture of these terminals.